Apparatus for cutting the strip at the tops of bags



w. FiscHER APPARATUS FOR CUTTING THE STRIP AT THE TOPS 0F BAGS Filed Sept. 30, 1954 2 Sheets-Sheet 1 FIG.

June 24, 1958 w. FISCHER APPARATUS FOR CUTTING THE STRIP AT THE TOPS OF BAGS Filed Sept. 50, 1954 2 Sheets-Sheet 2 INVQNTOR. Y 04d; hi e/- B 01 161 5? ATTORNEY United States Patent G APPARATUS FOR CUTTING THE STRIP AT THE TOPS OF BAGS Walter Fischer, Hellmuehle, Wildegg, Switzerland, assignor to Getreideflocken A. 6., Lenzhurg, Switzerland Application September 30, 1954, Serial No. 459,303

. Claims priority, application Switzerland October 1, 1953 2 Claims. (Cl. 16442) The present invention relates to apparatus for closing bags which are moved in succession along a predetermined path as well as to a process for closing such bags.

More particularly, the present invention relates to that type of bag whose top end is closed by an elongated strip which extends beyond the bag and is bent backwardly upon itself at its free ends, this strip housing within itself a wire or the like which may be torn from the strip to open the bag.

One of the objects of the present invention is to provide a process andapparatus according to which the strip at the top of a bag is automatically cut.

Another object of the present invention is to provide a process and apparatus according to which an elongated strip extending across a plurality of bags is automatically cut between each pair of successive bags to separate the latter from each other.

A further object of the present invention is to provide a process and apparatus according to which a strip extending across a row of bags is automatically cut at a predetermined distance in front of and behind each bag.

Also, it is an object of the present invention to provide an apparatus capable of accomplishing the above objects and being actuated byv the bags themselves.

An additional object of the present invention is to provide an exceedingly simple cutting means for cutting such a strip as well as a very simple control means actuated by the bags for controlling this cutting means.

With the above objects in view the present invention mainly consists of a process which includes the step of arranging the bags along a predetermined path, closing the top ends of the bags with an elongated strip extending continuously along the thus arranged bags, transporting the bags together along the path, and cutting completely across the strip at least once between each pair of successive bags during movement of the bags along a predetermined path by a stationary cutting apparatus which is located in the path of movement of the strip.

Furthermore, with the above objects in view the present invention mainly consists of an apparatus which includes a transporting means for transporting along a predetermined path a row of bags whose top ends are closed by a single continuous strip extending along and attached to the row of bags. Cutting means is located next to the path for cutting completely across the strip at least once between each pair of successive bags while the latter are moved along the path by the transporting means, and an actuating means is located in the path of the bags to be successively engaged by the latter for actuating the cutting means.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. This invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description when read in connection with the accompanying drawing, in which Fig. 1 shows in a fragmentary, schematic perspectiveview one possible apparatus constructed in accordance with the present invention and operating according to the process of the present invention. Fig. 2 is an electric wiring diagram illustrating one possible arrangement of electric control. 7

Referring now to the drawing, a transporting means 1 is provided to transport'the filled bags 2. It is pointed out that in this specification and in the claims which follow the term. bag is intended to cover all containers made of a flexible material and having open top ends which may be closed after filling of such containers. The transporting means 1 may simply be in the form of a belt guided by pulleys and driven in any suitable known way as by a motor or the like driving one of the pulleys.

The bags 2 are arranged in a row on the belt 1 in such a way that the top ends of the bags which are to be closed are located along a substantially straight line. A strip 19 extends along the tops of the successive bags to close the V latter, and this strip 19 is joined to the bags in a manner not illustrated and discussed below.

A cutting apparatus 3 is arranged adjacent the path of movement of the bags 2 and in particular adjacent the top ends of the bags. This cutting apparatus 3 includes a stationary support 4 formed with an elongated groove 5 and carrying a cutting blade 6. The cutting blade 6 is in the form of a two-armed lever pivotally carried on the support 4 by a pivot pin 7 fixed to the support 4 and extending through an opening of the cutting blade 6 intermediate the ends of the latter. I As is apparent from the drawing the cutting blade 6 is turnable in a vertical plane across the path of movement of the bags, and the blade 6 is provided witha cutting edge 6 which moves across the end of groove 5 visible in the drawing. The pin 7 is provided with anenlarged end against which an end of a coil spring 8 abuts, this coil spring being located about the pin 7 and pressing with its opposite end against the blade 6 to maintain the latter against the support 4.

The end of blade 6 opposite from its cutting edge 6 is pivotally connected to the bifurcated end 10 of a .rod 9 which is connected to the armature of an electromagnet 11, so that upon energizing of the electromagnet the armature will pull rod 9 to the right, as viewed in the drawing, to turn the blade 6 in a clockwise direction, so as. to move the cutting edge 6' thereof across the groove 5. A coil spring 12 is located about the rod 9, bears with one end against the end 10 of rod 9, and bears with its opposite end against the part 13 of the housing of solenoid 11 to urge the rod 9 against the action of the solenoid to the rest position shown in the drawing. i

The electromagnet 11 is electrically connected to an electric control apparatus 14, diagrammatically indicated in the drawing, which is operatively connected to a pair of feeler members 15 and 16. These feeler members 15 and 16 are in the form of levers which are actually switch operating members and they extend into the path of movement of the bags 2 in such a way that the moving bags themselves turn the feeler members 15 and 16 to actuate the switches 17 and 18 so as to control the control means 14 for actuating the solenoid 11.

Control apparatus 14 is a device which supplies an energizing pulse for the solenoid 11 by means of the conductors 20 when the levers 15 and 16 of the microswitches 17 and 18, respectively are in their on or oif positions. For example, control apparatus 14 can be a pulsing device which may include two thyratrons. When the switches are not actuated, the capacitors of the thyratron circuits in the control apparatus 14 are being charged. When the proper switch is actuated, the charged capacitor connected to the control grid of the thyratron fires the thyratron causing current flow therethrough.

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When the alternatof successive bags. Through properly choosing the distance between feeler 16 and the blade 6 it is possible to provide each bag with a strip portion 19" extending rearwardly therefrom. These portions 19' and 19" are ting blade will be returned to its inoperative position by ,1

the return spring 12. t

As is shown in the drawing, the switch-17 has a plate 25 fixed thereto, and a spring 26 is fixed at one end to the plate 25 and at its opposite end to the lever 15 for urging the latter to a rest position extending substantially normally across the path of movement of the bags. Elements identical with elements 25 and26 are fixed to the switch 18 and lever 16 for urging the latter'to a position also extending substantially normally across the path of movement of the bags. The switch 17 is opened when the switch operating member 15 extends across the path of movement of the bags andthe switch 18 is closed when the switch operating member l6-extends across the path of movement of the bags, switch 17 becoming closed when feeler 15 is moved by the bags to the position shown in the drawing and switch 18 becoming opened when feeler 16 is moved by the bags to a position out of the path of movement thereof.- Thus, switch 18 is closed only when the feeler member 16 is returned to its rest position extending across the path of movement of the bags. Each time one of the switches 17 and- 18 is closed the apparatus 14 completes a circuit to the magnet 11 for pulse energizing the latter to actuate the cutting blade 6. As is shown in the drawing, the leads 20 connect the control apparatus 14 electrically with the solenoid lland with the switches 17 and 18 while the lines 21 are electrically interconnected with the control apparatus 14. It is to be noted that the operation of control apparatus 14 is well known and does not, in itself, constitute a part of the present invention.

Another example of the electrical control means and its performance will be described below.

The above described structure operates as follows, in

accordance with the process of the invention:

The bagsZ are arranged on the transporting means 1 in the manner shown in the drawing and an uninterrupted closing strip 19 is folded along a central line and surroundsat the top edge of the strip 19 a wire 22. This strip '19 is folded and joined by guiding and pressure rollers to the bags 2 so that the strip 19 covers the top end of each bag and closes the same, the strip 19 being joined to the bags by glue or the like. The strip'19 moves together with the bags 2 through the slot 5 of the support 4. As soon as a bag 2 engages the first feeler 15, the latter is turned bythe bag itself from its switch opening position against the action of the relatively light spring 26 to the switch closingyposition which closes the switch 17 to pulse energize solenoid '11. In 'this way the blade 6 is turned to cut completely through the strip 19 being instantaneously returned, under the action of spring 12 to its initial open position. The location of switch 17 and lever 15 with respect to the support 4 is such that the strip 19 is not cut offnext' turns the feeler 16, but the switch 18 controlled thereby is. closed only when, the feeler16 returns to its starting position, and this happens only when the trailing edge 2' of each bag 'hasmoved beyond the feeler 16. Thus, upon return of feeler 16 to its starting position the switch.18 is closed and the magnet 11 is again pulse energized so that the strip 19 is then cut between a pair before.

bent backwardly upon the strip 19 to complete the closing of the bag and the wire 22 serves to retain the strip 19 in its thus folded position. Thewire 22 serves in a known way to open the bag after a part of the strip is torn away from the wire 22.

A very simple arrangement of electric control means is described now with reference to Fig. 2. This arrangement uses exclusively conventional electric components including switches and relays.

The relay diagram of Fig. 2 shows the switches 17 and 18 with their pertaining feelers 15 and 16 respectively, in their positions of rest, switch 17 being normally open and switch 18 being normally closed Besides this diagram contains five relays R R These relays are of conventional type and show their respective contacts in their normally open or normally closed position as the case may be. 7

In operation this circuit and control system works as follows:

Phase a: No bag has yet contacted the feelers 15 or 16, the switch 17 is in open position and switch 18 is in closed position. Now the main switch 2 is closed. Relay R is therefore energized and the contact 2 closed and held in this position. At the same time the solenoid 11 is energized via the contact d. of relay R The armature of solenoid 11 closes the contact I) of relay R This energizes the relay R Solenoid 11 is de-energized by the opening of contact d of relay R while the closing of contact 0 of the same relay establishes a circuit via contact e of relay R and the closed contact 1 of relay R so as to keep the relay R energized. In this manner the solenoid has been placed in a condition of inoperativeness for the rest of the duration of phase a. The knife 6 has actually carried out a cutting operation but this was cutting air because there is no strip yet in the position to be cut. Otherwise, this would have been a cut at the trailing edge of a bag at 19".

Phase b: The edge of the first bag contacts feelerlS and thereby closes contact 17. Relay R is energized and thereby opens the contact 1'. This interrupts the holding circuit that was established for relay R Relay R is deenergized and contact :1 closes. Thus the solenoid 11 is again energized via the still-closed switch 18. The knife blade 6 makes a trim cut at 19. The closing of contact [2 energizes relay R interrupts the circuit of solenoid 11 at contact d and establishes the holding circuit via contact c. However, since the closing of switch 17 has also energized the relays R and R the holding circuit for relay R is now established not via contact f but via the contact 11 of relay R At the same time a holding circuit for relay R is established via contact a of relay R and contact g of relay R Thus relay R remains energized and the armature of solenoid 11 remains in its position of rest. This condition remains unchanged up to the end of phase b. 7

Phase c: The front edge of the traveling bag now actuates lever 16 and thereby opens contact 18. This has only the effect of tie-energizing relay R and thereby opening contact e. But this contact is at present not active. Therefore nothing changes in the condition of the whole apparatus. Relay R is still held energized as This prevails up to the end of phase c.

Phase d: The rear end of the traveling bag releases feeler 15 and thereby causes opening of switch 17. Since now both switches 17 and 18 are in open position, the whole system is without electric current. All relays are deenergized. The armature of solenoid 11 is in position of rest. This practically completes the phase d and therewith one complete cycle of operation. At the end of this phase and cycle the rear end of the bag releases the feeler 16 of switch 18. Therefore at this moment the switch 18 is closed again and a new cycle starts exactly as at the beginning of this description when the main switch was being closed while switch 18 was in closed position.

The above described process, because it is controlled by the bags themselves, has the advantage of providing each bag with uniform strip portions 19' and 19" even if the bags are not uniformly arranged on the belt 1, and even if some bags are wider or narrower thanother bags, although the bags should be of approximately the same height. In this way, the same apparatus may be used with different size bags and with bags which are not necessarily located at the same distance from each other.

It is possible to substitute for an electronic control 14 an electromagnetic control.

It will be understood that each of the elements described above, or two or more together, may also find a. useful application in other types of bag closing processes and apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in strip cutting process and apparatus, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a bag closing apparatus, in combination, transporting means for transporting along a predetermined path a row of bags whose top ends are closed by a single continuous strip extending along and attached to the row of bags; cutting means located next to said path for cutting completely across said strip at least once between each pair of successive bags while the latter are moved along saidpath by said transporting means; a single elec-' tromagnetic operating means operatively connected to said cutting means for operating the same; electrical control means electrically connected to said operating means for controlling the latter with energizing impulses; a first switch located adjacent said path and connected electriwhy to said control means for impulse energizing the latter when said first switch is closed; first elongated switch operating means connected to said first switch for movement from a switch opening position, where said first switch operating means extends across the path of movement of the bags, to a switch closing position where the switch operating means has been engaged by a bag and moved thereby out of said path, whereby said control means is impulse energized by movement of said first switch operating means out of said path by a bag; a second switch located after said first switch along said path and connected electrically to said control means for impulse energizing the latter; a second elongated switch operating means connected to said second switch for movement from a switch closing position, where said second switch operating means extends across the path of movement of the bags, to a switch opening position where said second switch operating means has been engaged by a bag and moved thereby out of said path; and means connected to said second switch operating means for returning the same to said switch closing position thereof when said second switch operating means is not engaged by a bag so as to impulse energize said control means with said second switch when said second switch operating means extends across the path of movement of the bags.

2. In a bag closing apparatus, in combination, transporting means for transporting along a predetermined path a row of bags whose top ends are closed by a single continuous strip extending along and attached to the row of bags; cutting means located next to said path for cutting completely across said strip at least once between each pair of successive bags while the latter are moved along said path by said transporting means; a single electromagnetic operating means operatively connected to said cutting means for operating the same; electrical control means electrically connected to said operating means for controlling the latter with energizing impulses; a first switch located adjacent said path and connected electrically to said control means for impulse energizing the latter when said first switch is closed; first elongated switch operating means connected to said first switch for movement from a switch opening position, where said first switch operating means extends across the path of movement of the bags, to a switch closing position where the switch operating means has been engaged by a bag and moved thereby out of said path, whereby said control means is impulse energized by movement of said first switch operating means out of said path by a bag; a second switch located after said first switch along said path and connected electrically to said control means for impulse energizing the latter; a second elongated switch operating means connected to said second switch for movement from a switch closing position, where said second switch operating means extends across the path of movement of the bags, to a switch opening position where said second switch operating means has been engaged by a bag and moved thereby out of said path; and means connected to said second switch operating means for returning the same to said switch closing position thereof when said second switch operating means is not engaged by a bag so as to impulse energize said control means with said second switch when said second switch operating means extends across the path of movement of the bags, both of said elongated switch operating means being in the form of a pair of levers pivotally carried by said switches, respectively.

References Cited in the file of this patent 

